title: Loss mitigation in plasmonic solar cells: aluminium nanoparticles for broadband photocurrent enhancements in GaAs photodiodes.
abstract: We illustrate the important trade-off between far-field scattering effects, which have the potential to provide increased optical path length over broad bands, and parasitic absorption due to the excitation of localized surface plasmon resonances in metal nanoparticle arrays. Via detailed comparison of photocurrent enhancements given by Au, Ag and Al nanostructures on thin-film GaAs devices we reveal that parasitic losses can be mitigated through a careful choice of scattering medium. Absorption at the plasmon resonance in Au and Ag structures occurs in the visible spectrum, impairing device performance. In contrast, exploiting Al nanoparticle arrays results in a blue shift of the resonance, enabling the first demonstration of truly broadband plasmon enhanced photocurrent and a 22% integrated efficiency enhancement.
authors.affiliation: Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: N P
authors.initials: NP
authors.lastname: Hylton
authors.forename: X F
authors.initials: XF
authors.lastname: Li
authors.forename: V
authors.initials: V
authors.lastname: Giannini
authors.forename: K-H
authors.initials: KH
authors.lastname: Lee
authors.forename: N J
authors.initials: NJ
authors.lastname: Ekins-Daukes
authors.forename: J
authors.initials: J
authors.lastname: Loo
authors.forename: D
authors.initials: D
authors.lastname: Vercruysse
authors.forename: P
authors.initials: P
authors.lastname: Van Dorpe
authors.forename: H
authors.initials: H
authors.lastname: Sodabanlu
authors.forename: M
authors.initials: M
authors.lastname: Sugiyama
authors.forename: S A
authors.initials: SA
authors.lastname: Maier